M30B35 Swap FAQ

[harrypalmer]

Can any of you please share why on your most complete and helpful list, did not replace the E28 radiator for the E34?
Maybe I missed reading your intel on this. Anyhow, is it due to lack of physical space that kept you from properly install it? One would think the E34 radiator may have a larger capacity but of course don't know the answer to both questions, so would appreciate if you can share your thoughts. Thanks.

I simply didn't consider a new rad. Vlad's been driven hard in the heat and I have had zero cooling issues.

Thank you cek. Is Vlad's rad a OE BMW or Nissens unit? Been having some issues with my own South African and considering replacing it for now and for the upcoming swap.

[tig]

Can any of you please share why on your most complete and helpful list, did not replace the E28 radiator for the E34?
Maybe I missed reading your intel on this. Anyhow, is it due to lack of physical space that kept you from properly install it? One would think the E34 radiator may have a larger capacity but of course don't know the answer to both questions, so would appreciate if you can share your thoughts. Thanks.

I simply didn't consider a new rad. Vlad's been driven hard in the heat and I have had zero cooling issues.

Thank you cek. Is Vlad's rad a OE BMW or Nissens unit? Been having some issues with my own South African and considering replacing it for now and for the upcoming swap.

Dunno. I've never really paid attention to radiators. This is the best pic I could find of the one in Vlad. LOL.

[jayjaya29]

Thank you cek. Is Vlad's rad a OE BMW or Nissens unit? Been having some issues with my own South African and considering replacing it for now and for the upcoming swap.

This thread will be helpful to you:
viewtopic.php?p=1488053

[maybeillbuyit]

The spreadsheet I had used to track all parts for the M30B35 build/swap I did in Vlad.

https://1drv.ms/x/s!AsIgsqrZdRUOnCzzzFj ... P?e=Ipxh1u

This is great cek, thx for posting. Im in the planning stage for this ( maybe forever LOL)

[Riskybiz86]

Hi All,

I'm swapping my e28 535is (auto) to a to a m30b35 using a motronic 1.1 and harness that came with it from an '88 e24 L6 (auto). While I got the necessary fuse box connector conversion (thanks condor speed shop), I'm still a little fuzzy on how to make the right connections in the glove box (and it looks like someone responded to this in this thread but the pictures no longer load...).

Here's a picture of what I'm trying to figure out. Mainly how to wire the e24's connectors into the existing connector in the e28 glove box:

https://drive.google.com/file/d/1eePxcN ... sp=sharing

[willyv124]

Starting to go through my 1.3 auto harness from a e34. While rewrapping the harness I found a resistor that looks to be 100 ohms on the coolant temp gauge sender, not the cts for the ecu. Didn't find anything on google or mye28 about this. I know some 533's might have had a resistor on the cts for the ecu, but seems weird to find this on a 1.3 harness on the sender side. Anyone else come across this?

[Joey28]

I know this is a M30B35 swap thread, but since so much of it concerns swapping over to Motronic 1.3 also, a word to M30B32 owners: I have an '83 M30B32, with the old style oscillating plate AC compressor and big mounting bracket, which gets in the way of the Motronic 1.3 crank sensor bracket. I tried using the old original 1.0 TDC reference sensor bracket, but realized it's at the wrong clock position. So I ended up having to carefully grind a small clearance notch in the AC bracket. I also had to massage the upper adjusting arm to clear the top of the 1.3 sensor and bracket. The AC brackets are beefy so hopefully I haven't compromised their strength much. Tried to keep the grind smooth to avoid stress risers in the metal.

[bert poliakoff]

If you get sorted and the ecu is a 002 I could be interested in as I have Motronic 1.0 and a spare could be a good thing to have on the shelf

[trancher]

as I understand it, no one has converted e28EH to motronik 1.3 successfully?

by vintagemotorsportsofMD » Jun 08, 2011 9:53 PM

I just did this conversion, if anyone needs help PM me with specifics and I will be glad to help. It took hours and hours poking through all the diagrams and ETK to get my setup to work perfectly. You do need to use the round plug TPS in the conversion, you also need a viable e28 auto engine harness to cut open and take the entire shielded TPS switch wire out of and spice into the round 1.3 auto TPS connector. You also need to supply the TCU with 5v. The vain air meter ref voltage output is perfect to snag the 5v needed there, as the 1.3 motronic does not have a 5v output for the TCU or "AEGS" I believe they started calling it. As I said, if anyone has any specific questions feel free to PM me. I don't have a time to make a nice neat post at this point, but I will add a photobucket page of pics when I can remember to bring my camera home...

this man apparently could, but where is he now and how to contact him?

[aargilb]

I have done the 1.3 swap with EH automatic. I have an 86. Let me know what questions you have.

[trancher]

what transmission control unit (TCU) did you use? TCU and DME number please. How do you feel about this swap?

[aargilb]

I used the transmission control unit that came with my 1986 535i. The ecu was a Bosch 0261200179 for motronic 1.3.

I did this swap to correct the idle and get better gas mileage. It worked. Car runs better, smoother, idles better. Best improvement I made to the car. I am still running my M30B34. I plan to upgrade to a M30B35 eventually.

[trancher]

Can show me automatic transmission control unit you used? you can also write his number

[aargilb]

I have a 1986 535i with a 10/1985 build date. You should be able to get the TCU number off realoem.com

[Billwiththeb]

New to the group. Hello..so I've got a 733i 84 3.2/3.5 In her..my cam n lifters are toast..oil rail bolt issue..so I got a 3.5 cheep and want to know can the 3.5 cam drop in the 3.2 and lifters????why do this..heads are off and it's what I've got..yes I'm aware the 3.5 cam has more lift..will I have piston/valve clearance is my main question??thanks for any help..

[1st 5er]

Merry Christmas, y'all.

[willyv124]

I"ve read through this a few different times and i'm working on my 1.3 harness again getting ready for install. Trying to clarify something about the wiring diagram here



For the c103 wiring. it says

e28 c103....e34 c101....e34 dme
pin 1...........pin 9..........pin 6
pin 3...........pin 8..........pin 32

i.e.
pin 1 = pin 9 = pin 6
pin 3 = pin 8 = pin 32

and when looking at the ETM that works out for c103 pin 1


but when looking at the ETM for pin 8 and pin 32, they don't match. pin 8 of e34 c101 goes to pin 38 of the dme, pin 3 of e34 c101 is actually what goes to pin 32.



Looking at this, it does seem clear that pin 3 is actually what i want to get the fuel economy.
https://www.e30zone.net/e30wiki/index.p ... tronic_1.3

Can someone shed some light on this? Have I missed this in thread already?

[trancher]

Purveyor of these just replied to my inquiry:



I'm def getting one.

I installed this over the weekend, and it works great.



I installed it on the female side of C103, inline with the WT/BK wire that goes to the OBC. For power, I used a spare 12V from the main relay that was part of the B35 harness and was unused. For ground, I used the ground for the flashlight charger.

The potentiometer lets you adjust the signal to the OBC/econometer:

Keep the adjustment knob in the middle to start and get an idea of where your corrected mileage stands. Turning it to the left will increase your displayed mileage, turning it right will decrease displayed mileage.

I started with it all the way to the right and I showed 7-8mpg after a 4-5 mile drive. Then, with it all the way to the left, I showed 26pmg on the same loop. Putting it roughly in the middle it then showed 15mpg.

A few tankfuls of fuel and it will be easy to dial in. Great product; would buy again.

What is this thing called, is there any information, and where can I buy it?